Comprehensive System Identification of Ducted Fan UAVs - Cal Poly

adequate way to characterize the different pitching moment characteristics for thesevehicles. It is can be seen that the derivatives for the i-Star class of vehicles differconsiderably from the other ducted fans analyzed. In the case of the wind tunnel resultsfor these two vehicles, the 9” value (2.45 x 10 -5 ) and the 29” value (5.20 x 10 -5 ) are of thesame order of magnitude, but an order lower than all of the other vehicles. This suggeststhat there may be something unique about the i-Star design, or that there was somethingunexplainable happening with the wind tunnel tests of the vehicles. Flight test revealedthat the 9” vehicle actually had a very large value for M u (3.80 x 10 -3 ). This is an orderlarger than the other vehicles, and a full two orders greater than the wind tunnel resultsfor the same vehicle. This could be due to the fact that M u was found to be so dominant inthe identification.To briefly summarize and conclude, all four of the ducted fan vehicles exhibitlikeness in pitching moment characteristics. The only anomaly seen is with the i-Starvehicle which shows relatively higher and lower C Mu values in comparison to the othervehicles and the method of identification.- 55 -